org.hibernate.annotations.Comment Maven / Gradle / Ivy

Go to download

Show more of this group Show more artifacts with this name
Show all versions of beangle-hibernate-core Show documentation

Hibernate Orm Core Shade,Support Scala Collection

There is a newer version: 6.6.2.Final

Show newest version

/*
 * Hibernate, Relational Persistence for Idiomatic Java
 *
 * License: GNU Lesser General Public License (LGPL), version 2.1 or later.
 * See the lgpl.txt file in the root directory or .
 */
package org.hibernate.annotations;

import org.hibernate.binder.internal.CommentBinder;

import java.lang.annotation.Repeatable;
import java.lang.annotation.Retention;
import java.lang.annotation.Target;

import static java.lang.annotation.ElementType.FIELD;
import static java.lang.annotation.ElementType.METHOD;
import static java.lang.annotation.ElementType.TYPE;
import static java.lang.annotation.RetentionPolicy.RUNTIME;

/**
 * Specifies a comment that will be included in generated DDL.
 * 
 * By default, if {@link #on} is not specified:
 * 

 * when a field or property is annotated, the comment applies to the mapped column,
 * 
when a collection is annotated, the comment applies to the collection table, and
 * 
when an entity class is annotated, the comment applies to the primary table.
 * 
 * 
 * But when {@link #on} is explicitly specified, the comment applies to the mapped table
 * or column with the specified name.
 * 

 * For example:
 * 
 * @Entity
 * @Table(name = "book")
 * @SecondaryTable(name = "edition")
 * @Comment("The primary table for Book")
 * @Comment(on = "edition",
 *          value = "The secondary table for Book")
 * class Book { ... }
 * 
 *
 * @apiNote In principle, it's possible for a column of a secondary table to have the
 *          same name as a column of the primary table, or as a column of some other
 *          secondary table. Therefore, {@link #on} may be ambiguous.
 *
 * @author Yanming Zhou
 * @author Gavin King
 */
@TypeBinderType(binder = CommentBinder.class)
@AttributeBinderType(binder = CommentBinder.class)
@Target({METHOD, FIELD, TYPE})
@Retention(RUNTIME)
@Repeatable(Comments.class)
public @interface Comment {
	/**
	 * The text of the comment.
	 */
	String value();

	/**
	 * The name of the table or column to add the comment to.
	 */
	String on() default "";
}